PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 16469751-1 2005 The first and rate-limiting step in the biosynthesis of steroid hormones is the transfer of cholesterol into mitochondria, which is facilitated by the steroidogenic acute regulatory (StAR) protein. Steroids 56-72 steroidogenic acute regulatory protein Mus musculus 183-187